Automatic sprinkler head

ABSTRACT

A sprinkler head including a body member having a central orifice and downwardly extending supporting arms converging to form a bearing point with the central body orifice adapted to receive nozzles having discharge ports of different sizes and adapted to be sealed by a valve member. A temperature-responsive assembly is mounted between the valve member and bearing point in an offset relation and includes a triangular-shaped strut member, a triangular-shaped intermediate member connected to the strut member by fusible material, and a spring member connected at one end to the intermediate member with the other end of the spring member bearing against the bearing point and supporting the strut member at a point offset from the bearing point.

United States Patent Asp 1 July 29, 1975 [54] AUTOMATIC SPRINKLER HEAD 2,414,127 1/1947 Shaw 169/39 UX 3,770,063 11 1973 .l l' 1694 [76] Inventor: Ingemar B. Asp, Beach Rd., u lam 2 X NY. 10562 Ossmmg Primary Examiner-Robert S. Ward, Jr. Filedi ebll, 1974 Attorney, Agent, or Firm-Amster & Rothstein [21 Appl. NO.Z 441,411

[57] ABSTRACT [52] U.S. Cl. 169/39; 169/42; 239/391 A sprinkler head including a .body member having a [51] Int. Cl... A62c 37/30; A620 37/12; B05b 15/08 central orifice and downwardly extending supporting [58] Field of Search 169/37-42; arms converging to form a bearing point with the cen- 239/461, 569, 390, 391, 397, 600, 596 tral body orifice adapted to receive nozzles having discharge ports of different sizes and adapted to be [56] References Cited sealed by a valve member. A temperature-responsive UNITED STATES PATENTS assembly is mounted between the valve member and 488,003 12/1892 Gilmore 169/40 bearmg pomt m an Offset and mcludes a 783 969 2/1905 Mam I I 169/39 gular-shaped strut member, a triangular-shaped lnter- LO7QII36 11/1918 Long v 169/39 mediate member connected to the strut member by 1,160,; 11/1915 Human 169/39 fusible material, and a spring member connected at 1,165,313 12/1915 Bower 169/39 n n o he intermediate member with the other 1,195,201 8/1916 Garrett 169/39 end of the spring member bearing against the bearing 1,261,873 4/1918 Townsend 169/39 point and supporting the strut member at a point off- 1 412,172 4 1922 Duley 169/39 Set f the bearing poim 1,432,386 lO/l922 Curney t 1 1 169/37 2,2778] 1 3/1942 Ashley et a1. 239/391 X 13 Claims, 8 Drawing Figures SHEET PATENTEDJuL29l975 1 AUTOMATIC SPRINKLER HEAD ber seated within the discharge port, a temperatureresponsive assembly including fusible material is normally forced between the valve member and a bearing frame forming part of the body. Accordingly, when the temperature within the vicinity of the temperatureresponsive assembly reaches a predetermined level, the fusible material which holds the temperatureresponsive assembly together begins to fuse causing the temperature-responsive assembly to fall away from the valve member. The fluid under pressure is then capable of unseating the valve member to allow the fluid to be dispersed through the discharge port formed in the body.

Sprinkler heads of the type described are well-known and function in a generally satisfactory manner. However, they do include some drawbacks which'could be improved upon. For example, such sprinkler heads are of a relatively large size, are very conspicuous when installed in walls or ceilings, and are unattractive in appearance. Although the unattractive appearance of sprinkler heads is not normally a critical factor for industrial applications, such as infactories, such'large and conspicuous sprinkler heads do present a problem in homes and offices where their unattractive appearance interferes with decorating schemes and the like.

In addition, such sprinkler heads are difficult to accurately assemble and are not capable of adjustment. Typically, to install the temperature-responsive assembly within the body of the sprinkler head, the temperature-responsive assembly must be compressed and forced between the valve member and the bearing frame so that the sprinkler head body will'apply the correct amount of tension to the temperatureresponsive assembly. Accordingly, the components of the temperature-responsive assembly and sprinkler head must be manufactured to meet specific and exacting tolerances so that when the temperature-responsive assembly is installed the correct amount of tension will be applied thereto by the body, Obviously, this greatly increases the cost of manufacture. Moreover, once the temperature-responsive assembly is installed within the sprinkler head, if the tension applied thereto does not meet the design specifications, there is no simple and accurate way that the tension can be adjusted. Typically, to overcome such a problem in the'past, the bearing frame hasbeen adjusted with 'respect'to the body in order to adjust the tension applied to the temperatureresponsive assembly. Obviously, this is a rather crude and inaccurate method of adjustment and increases the cost of manufacture. v

Accordingly, it is an overall object of the present invention to provide an automatic sprinkler head which overcomes one or more of the aforesaid difficulties. In its assembled configuration, the sprinkler head is compact in size, inconspicuous when installed and attractive in appearance so that it may be used in homes and offices and not interfere with decorating schemes. In its commercial form, the sprinkler head is of relatively simple construction, is readily manufactured by mass production techniques at relatively low cost and includes a number of simple and relatively indestructible components.

It is also an object of the present invention to provide an automatic sprinkler head which includes a temperature-responsive assembly which may be easily assembled and installed in the sprinkler head and the tension applied thereto may be adjusted in a simple manner so that the components donot require the exacting manufacturing tolerances required in the past.

It is a'further object of the present invention to pro vide a temperature-responsive assembly for a sprinkler head having components which are relatively flat and therefore inexpensive to manufacture and which include large solderreceiving areas to decrease the separating force per unit of area applied to the solder. This, in turn, substantially decreases the problem of cold flow. I

It is a still further object of the present invention to provide an automatic sprinkler head which is capable of receiving nozzles having discharge ports of different sizes so that one size sprinkler head may be manufactured to meet a wide range of design requirements by merely changing different nozzles.

In accordance with an illustrative embodiment demonstrating objects and features of the present invention, there is provided an automatic sprinkler head which includes a body member having a central orifice adapted to be connected to a conduit or the like which is connected to a source of fluid under pressure. Downwardly extending supporting arms are integrally formed with the body member and converge to form a bearing cone or pivot point and also support a spray deflector. The central 'orifice'of the body is adapted to receive nozzles having different size discharge ports to meet different design requirements with the nozzle having a valve seat formed in one end thereof. A disc and cap form a valve member which is adapted to be seated and held within the valve seat of the nozzle by a temperature-responsive assembly which is compressed between the valve member and the bearing or pivot point. The temperature-responsive assembly includes a triangularshaped strut member, a triangular-shaped intermediate member connected to the strut member by suitable fusible material, and a spring member connected at one end to the intermediate member with the other end of the spring member seated on the bearing point. One end of the strut member is adapted to be seated in the valve member and the other end of the strut member is adapted to bear against the spring member in an offset relation to the bearing or pivot point. The strut member and intermediate member include relatively wide and flat faces which form a wide gap therebetween for receiving fusible material which serves to decrease the separating force per unit of area applied to the fusible material and thereby decreases the problem of cold flow.

To assemble the sprinkler head of the present invention, a suitable nozzle having a discharge port of an appropriate size to meet the particular design requirements is selected and partially threaded into the central orifice of the body. The valve member is then inserted within the nozzle to cooperate with the valve seat and seal the discharge port and the temperature-responsive assembly is then assembled for insertion between the valve member and the bearing point. The nozzle is then threaded further downwardly within the central orifice until it applies the required tension against the temperature-responsive assembly which is resisted by the bearing cone. Due to the offset mounting relation of the temperature-responsive assembly, a horizontal component of force is applied thereto tending to separate the strut member and the intermediate member with the separating force being resisted by the fusible material. Accordingly, as the amount of heat around temperature-responsive assembly begins to rise and reaches a predetermined level, the fusible material will begin to fuse and the horizontal separating force will operate to separate the strut member from the intermediate member. As the strut member is no longer supported, it will fall away allowing the fluid under pressure to unseat the valve member from the discharge port ofthe nozzle. The fluid will then shoot out through the nozzle and impinge the spray deflector so that it may be deflected and sprayed over a large area.

Advantageously, the temperature-responsive assembly of the present invention is extremely compact in size allowing the overall sprinkler head to be very compact so that when installed, it is inconspicuous and attractively blends with the decorating scheme. In addition, the temperature-responsive assembly is easy to assemble and install between the valve member and bearing point with the desired tension being applied thereto by simply adjusting the nozzle. Further, as the sprinkler head of the present invention is designed to accept nozzles having discharge ports of different sizes, one size sprinkler head can be manufactured to receive a series of nozzles having different size discharge ports in accordance with particular design requirements.

The above description as well as further objects, features and advantages of the present invention will be more fully understood by reference to the following detailed description of the presently preferred, but nontheless illustrative embodiment in accordance with the present invention, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is an exploded perspective view of the sprinkler head of the present invention in its disassembled configuration;

FIG. 2 is a perspective view illustrating the fusible material-receiving members which form a part of the temperature-responsive assembly of the present invention;

FIG. 3 is a perspective view illustrating the spring member which forms a part of the temperatureresponsive assembly;

FIG. 4 is an exploded view in section illustrating the installation of the temperature-responsive assembly between the valve member and bearing point;

FIG. 5 is a sectional view illustrating the temperature-responsive assembly of the present invention installed between the valve member and bearing point;

FIG. 6 is an enlarged sectional view illustrating the sprinkler head of the present invention assembled and installed within a ceiling or a wall;

FIG. 7 is an enlarged sectional view, taken substantially along the line 77 in FIG. 6 and looking in the direction of the arrows, illustrating the temperatureresponsive assembly falling away from the sprinkler head allowing the fluid under pressure to unseat the valve member from the discharge port of the nozzle; and

FIG. 8 is a sectional view illustrating the nozzle of the present invention in detail.

Referring now specifically to the drawings and in particular to FIG. 6, there is shown an illustrative sprinkler head embodying features of the present invention, generally designated by the reference numeral 10, which includes a frame 12 having a main body 14 and downwardly extending supporting arms 16 integrally formed therewith which converge to form a bearing cone or point 18. A suitable spray deflector 20, for a purpose to be explained, is connected to the base of bearing cone 18 in any suitable manner.

Sprinkler head 10 is adapted to be mounted in any appropriate location to disperse fluid under pressure and in this illustrative form of the invention, in which the sprinkler head is particularly designed for extinguishing fires, sprinkler head 10 is mounted within an opening 22 formed in a ceiling 24. In order to provide an aesthetic and finished appearance to the mounting of sprinkler head 10 within ceiling opening 22, an escutcheon plate 26 having tabs 26a is adapted to slidably engage main body 14 of sprinkler head 10. Escutcheon plate 26 is movable relative to main body 14 so that after sprinkler head 10 has been installed, escutcheon plate 26 may be adjusted so that it is flush with and bears against ceiling 24 in order to provide a finished and pleasing appearance to the installation. Main body 14 is also provided with abutments 14a which correspond in number to tabs 26a formed on escutcheon plate 26 and main body 14 and escutcheon plate 26 are adapted to be assembled so that abutments 14a and tabs 26a are in alignment. In this manner, when sprinkler head 10 and escutcheon plate 26 are installed, the engagement of tabs 26a with abutments 14a prevent escutcheon plate 26 from sliding further upwardly along main body 14.

As shown most clearly in FIG. 6, main body 14 is provided with an orifice 30 which extends through the center thereof and which consists of a wide orifice 32 lead-v ing into a narrow orifice 34, both being internally screw-threaded. Wide orifice 32 is adapted to be attached to a conduit 36 or the like which is connected to a source of fluid under pressure. Narrow orifice 34 is adapted to receive an externally screw-threaded nozzle 38 having a valve seat 38a and a discharge orifice or port 38b. As may be seen most clearly in FIGS. 7 and 8, narrow orifice 34 is adapted to receive a nozzle 38 having an external diameter of size B. However, the internal diameter of the discharge orifice or port 38b of nozzle 38 may vary in accordance with the particular design requirements of the installation. More particularly, as shown in FIGS. 7 and 8, the internal diameter of discharge port 38b may be of size a, or the internal diameter may be more than or less than size a. In this manner, one size sprinkler head can be modified to meet any design requirements by installing a nozzle 38 within narrow orifice 34 which has a discharge port 38b of a size to meet the particular design requirements. Advantageously, it would only be necessary to manufacture one size sprinkler head 10 which would be universal to receive a series of nozzles 38 having discharge ports 38b which vary in size in accordance with the particular design requirements.

To control the flow of fluid through central orifice 30 and nozzle 38, a valve member 40 is adapted to cooperate with valve seat 38a formed on nozzle 38. As shown most clearly in FIGS. 1 and 4, valve member 40 includes a disc 42 adapted to mate with a cap 44. More particularly, disc 42 is formed with a circular depression 42a and cap 44 is provided with a circular lip 440 which is adapted to be inserted into and mate with depression 42a formed in disc 42. In addition, as may be seen in FIG. 6, depression 42a of disc 42 is formed to be of an appropriate external diameter to fit within and cooperate with valve seat 38a formed on nozzle 38. Further, the lower suface of cap 44 is also provided with a cap seat 44b in the form of a cutout or slot, for a purpose to be explained.

In the particular embodiment illustrative of the present invention, valve member 40 is normally held in seating relation within valve seat 38a of nozzle 38 by means of a temperature-responsive assembly 50 which includes a strut member 52, an intermediate member or connecting link 54 connected to strut member 52 by any suitable fusible material 56, such as solder, and a spring member 58. Temperature-responsive assembly 50 is adapted to be mounted in an offset relation, that is, offset from a central axis 60 defined by cap seat 4412 and bearing point 18, for a purpose to be explained. More particularly, as shown most clearly in FIGS. 2, 4 and 6, strut member 52 is generally triangular in configuration and includes a tab 52a formed at its upper end having an upper edge 52b adapted to be inserted within cap seat 44b. Upper edge 52b is rounded to prevent strut member 52 from becoming wedged in cap seat 44b upon operation. Strut member 52 also includes a bevelled edge 520 formed at its opposite lower end to minimize contact with spring member 58.

Intermediate member 54 includes a horizontally extending link portion 54a having a rectangular-shaped hole 54b formed therein and also includes a generally triangular-shaped vertical plate 540 having a plurality of dimples 54d formed therein, and constructed to be substantially perpendicular to link 54a. Dimples 54d are formed in vertical plate 540 to form and maintain a gap between strut member 52 and vertical plate 54c, with the gap serving to receive a suitable fusible material 56, such as solder. In this illustrative form of the invention, dimples 54d maintain a 0.003 inch solder gap between strut member 52 and vertical plate 54c.

Spring member 58 is of a generally L-shaped configuration and includes a vertical portion 58a which is of a generally triangular configuration and a horizontal portion 58b having dimples 580 formed therein. Vertical portion 58a of spring member 58 includes an upper tip 58d which is adapted to be inserted through the rectangular-shaped hole 54b formed in intermediate member 54. In addition, as shown most clearly in FIG. 4, dimples 58c form an upper recess or groove 582 and a lower recess or groove 58f. Lower recess 58fis adapted to receive and bear against bearing point 18, while upper recess 58e is adapted to receive the bevelled lower edge 52c of strut member 52. In this manner, as shown in the assembled configuration in FIG. 5, strut member 52 will be slightly offset from central axis 60, defined by cap seat 44b and bearing point 18, by a distance equal to the space between bearing point 18 and the point at which bevelled edge 52c makes contact with upper recess 58e. This offset distance is maintained at a minimum to insure that there will be only a small force component in the horizontal direction, that is, a force in a direction perpendicular to central axis 60, tending to separate strut member 52 and intermediate member 54, which separating force is resisted by fusible material 56. As will be explained below, this separating horizontal component of force is derived from assembling sprinkler head 10 by advancing nozzle 38 and applying a tension load against temperatureresponsive assembly 50.

In order to provide a clear-understanding of the present invention, a description of the assembly, installation and operation of the sprinkler head of the present invention will now be given. To assemble sprinkler head 10, a suitable nozzle 38 having a discharge port 38b of an appropriate size to meet the particular design requirements is selected and partially threaded into narrow orifice 34. Valve member 40 is then assembled by inserting cap 44 within disc 42. The circular depression 42a of disc 42 is then inserted within nozzle 38 to cooperate with valve seat 38a and seal discharge port 38b. Next, temperature-responsive assembly 50 is assembled for insertion between cap 44 and bearing cone 18. More particularly, the upper tip 58d of spring member 58 is inserted through the rectangular-shaped hole 54b formed in intermediate member 54 and, simultaneously, bevelled lower edge 52c of strut member 52 is inserted within upper recess or groove 58e. To install temperature-responsive assembly 50 within sprinkler head 10, upper edge 52b of strut member 52 is inserted within cap seat 44b and lower recess 58f of spring member 58 is placed over bearing point 18. Then, while holding temperature-responsive assembly 50 between cap 44 and bearing point 18, nozzle 38 is threaded further downwardly within narrow orifice 34. In this manner, valve member 40 will be firmly seated within valve seat 38a of nozzle 38, upper edge 52 b of strut member 52 will be firmly seated with cap seat 44b, and lower recess 58f of spring member 58 will firmly bear against bearing point 18 to maintain temperatureresponsive assembly 50 in an offset relation, offset from central axis 60. In this illustrative form of the invention, nozzle 38 is threaded downwardly within narrow orifice 34 until it applies one hundred pounds of force against temperature-responsive assembly 50, which one hundred pound load is resisted by bearing cone 18 of frame 12. In addition, in this illustrative form of the invention, the distance between link portion 540 and bearing point 18 along central axis 60 is approximately seventeen times greater than the offset distance, that is the distance equal to the space between bearing point 18 and the point at which bevelled edge 52c of strut member 52 makes contact with upper recess 58e. Thus, this 17 to 1 distance ratio determines that a 17 to I force ratio will be applied along the vertical and horizontal axes, respectively, of the temperature-responsive assembly 50. Accordingly, as the vertical component of force being applied along central axis 60 by nozzle 38 is one hundred pounds, the separating horizontal component of force tending to separate strut member 52 and intermediate member 54 is approximately six pounds, as determined by the 17 to I force ratio. However, this six pound separating force is resisted by fusible material 56. Advantageously, strut member 52 and intermediate member 54 include relatively wide faces for receiving fusible material 56 which serves to distribute the 6 pound separating force over a large area of fusible material and thereby decreases the separating force per unit of area applied to fusible material 56.

This, in turn, substantially decreases the problem of cold flow.

Accordingly, as the amount of heat around temperature-responsive assembly 50 begins to rise, fusible material 56, such as solder, will begin to fuse at a predetermined temperature. As soon as fusible material 56 melts sufficiently, the six pound horizontal separating force will operate to separate strut member 52 and intermediate member 54 as shown in FIG. 7. This will cause intermediate member 54 and spring member 58 to fall away from strut member 52. As strut member 52 is no longer supported, it will fall out of cap seat 44b, thereby releasing valve member 40. The fluid under pressure contained within conduit 36 and nozzle 38 will then cause valve member 40 to be unseated from valve seat 38a in nozzle 38. The fluid under pressure will then be free to pass throughconduit 36 and nozzle 38 at a velocity determined by the internal diameter of discharge port 3812. The fluid will then shoot out through nozzle 38 and impinge spray deflector so that the fluid may be deflected and sprayed over a very large area. In this illustrative form of the invention, the fluid under pressure is of the type used for fire extinguishing and it will operate to extinguish the fire in the area below sprinkler head 10.

From the foregoing, it will be appreciated that there has been provided in accordance with the present invention an improved automatic sprinkler head which is compact in size and attractive in appearance, which is easy to assemble and install, which includes a nozzle movable within the bodys central orifice so that the tension applied to the temperature-responsive assembly may be easily adjusted, which includes a temperature-responsive assembly having components which are relatively flat and inexpensive to manufacture, which includes a temperature-responsive assembly having large solder-receiving areas to decrease the force per unit of area applied to the solder and therefore substantially decreases the problem of cold flow, and a sprinkler head which is adapted to receive a series of nozzles having different size discharge ports.

A latitude of modification, change and substitution is intended in the foregoing disclosure. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the spirit and scope of the present invention.

What is claimed is:

1. A sprinkler head adapted to be attached to a supply of fluid under pressure comprising a body having an internal thread, an orifice extending therethrough to allow said fluid to pass through said body, means for connecting said body to said fluid supply, an externally threaded nozzle having an orifice, said nozzle being constructed and arranged to be threaded within said internal thread of said body with said nozzle orifice in communication with said body orifice, valve means for closing said nozzle orifice, a support member extending downwardly from said body and forming a central bearing point, said valve means and said bearing point defining a central axis, temperature-responsive means supported between said valve means and said bearing point and being offset from said central axis, said temperature-responsive means including a strut member, a spring member and an intermediate member connecting said strut member and said spring member, one end of said strut member engaging said valve means and the other end of said strut member bearing against said spring member and said bearing point at a point offset from said central axis, said nozzle and said body being constructed and arranged for adjustment of said nozzle to apply tension to said temperatureresponsive assembly between said valve means and said bearing point, said strut member and said intermediate member including faces forming a gap therebetween for receiving fusible material in said gap for connecting said strut member and said intermediate member, said fusible material adapted to fuse at a predetermined temperature and disconnect said strut member and said intermediate member thereby releasing said tension on said temperature-responsive assembly and on said valve means to allow the fluid under pressure to pass through said body and said nozzle orifices.

2. A sprinkler head in accordance with claim 1 wherein said body is adapted to receive nozzles having different size discharge orifices.

3. A sprinkler head in accordance with claim 1 wherein said intermediate member includes a vertical plate having a plurality of dimples to form and maintain said fusible material-receiving gap between said strut member and said vertical plate.

4. A sprinkler head in accordance with claim 1 wherein said spring member is generally L-shaped in configuration with one end thereof adapted to engage one end of said intermediate member and the other end of said spring member adapted to engage and bear against said bearing point.

5. A sprinkler head in accordance with claim 1 wherein said strut member includes a tab formed at one end for insertion into said valve means and a bevelled edge formed on the other end for engaging and maintaining minimum contact with said spring member.

6. A sprinkler head in accordance with claim 1 wherein said fusible material-receiving faces of said strut member and said intermediate member are substantially triangular in configuration.

7. A sprinkler head in accordance with claim 1 wherein said intermediate member includes a link connecting said face of said intermediate member to one end of said spring member.

8. A sprinkler head in accordance with claim 7 wherein said link includes a hole for receiving one end of said spring member.

9. A method of assembling a sprinkler head adapted to be attached to a supply of fluid under pressure including a body having an orifice extending therethrough to allow the fluid to pass through said body, a valve member for closing the body orifice and a support member extending downwardly from the body and forming a bearing frame comprising the steps of inserting a nozzle having a discharge port within said body orifice, placing said valve member in a valve seat formed in said nozzle, assembling a temperatureresponsive assembly, inserting said temperatureresponsive assembly between said valve member and said bearing frame, and tightening said nozzle against said valve member to apply tension to said temperature-responsive assembly so that said temperatureresponsive assembly bears against said bearing frame.

10. A method of assembling a sprinkler head in accordance with claim 9 wherein the step of inserting said nozzle within the body orifice includes the step of threading said nozzle relative to the body orifice.

11. A method of assembling a sprinkler head in accordance with claim 9 wherein the step of assembling steps of engaging one end of said strut member with said valve member and engaging one end of the spring member with said bearing frame.

13. A method of assembling a sprinkler head in accordance with claim 9 wherein the step of tightening said nozzle includes the step of threading said nozzle relative to said body orifice. 

1. A sprinkler head adapted to be attached to a supply of fluid under pressure comprising a body having an internal thread, an orifice extending therethrough to allow said fluid to pass through said body, means for connecting said body to said fluid supply, an externally threaded nozzle having an orifice, said nozzle being constructed and arranged to be threaded within said internal thread of said body with said nozzle orifice in communication with said body orifice, valve means for closing said nozzle orifice, a support member extending downwardly from said body and forming a central bearing point, said valve means and said bearing point defining a central axis, temperatureresponsive means supported between said valve means and said bearing point and being offset from said central axis, said temperature-responsive means including a strut member, a spring member and an intermediate member connecting said strut member and said spring member, one end of said strut member engaging said valve means and the other end of said strut member bearing against said spring member and said bearing point at a point offset from said central axis, said nozzle and said body being constructed and arranged for adjustment of said nozzle to apply tension to said temperature-responsive assembly between said valve means and said bearing point, said strut member and said intermediate member including faces forming a gap therebetween for receiving fusible material in said gap for connecting said strut member and said intermediate member, said fusible material adapted to fuse at a predetermined temperature and disconnect said strut member and said intermediate member thereby releasing said tension on said temperature-responsive assembly and on said valve means to allow the fluid under pressure to pass through said body and said nozzle orifices.
 2. A sprinkler head in accordance with claim 1 wherein said body is adapted to receive nozzles having different size discharge orifices.
 3. A sprinkler head in accordance with claim 1 wherein said intermediate member includes a vertical plate having a plurality of dimples to form and maintain said fusible material-receiving gap between said strut member and said vertical plate.
 4. A sprinkler head in accordance with claim 1 wherein said spring member is generally L-shaped in configuration with one end thereof adapted to engage one end of said intermediate member and the other end of said spring member adapted to engage and bear against said bearing point.
 5. A sprinkler head in accordance with claim 1 wherein said strut member includes a tab formed at one end for insertion into said valve means and a bevelled edge formed on the other end for engaging and maintaining miniMum contact with said spring member.
 6. A sprinkler head in accordance with claim 1 wherein said fusible material-receiving faces of said strut member and said intermediate member are substantially triangular in configuration.
 7. A sprinkler head in accordance with claim 1 wherein said intermediate member includes a link connecting said face of said intermediate member to one end of said spring member.
 8. A sprinkler head in accordance with claim 7 wherein said link includes a hole for receiving one end of said spring member.
 9. A method of assembling a sprinkler head adapted to be attached to a supply of fluid under pressure including a body having an orifice extending therethrough to allow the fluid to pass through said body, a valve member for closing the body orifice and a support member extending downwardly from the body and forming a bearing frame comprising the steps of inserting a nozzle having a discharge port within said body orifice, placing said valve member in a valve seat formed in said nozzle, assembling a temperature-responsive assembly, inserting said temperature-responsive assembly between said valve member and said bearing frame, and tightening said nozzle against said valve member to apply tension to said temperature-responsive assembly so that said temperature-responsive assembly bears against said bearing frame.
 10. A method of assembling a sprinkler head in accordance with claim 9 wherein the step of inserting said nozzle within the body orifice includes the step of threading said nozzle relative to the body orifice.
 11. A method of assembling a sprinkler head in accordance with claim 9 wherein the step of assembling a temperature-responsive assembly includes the steps of connecting a strut member to an intermediate member with fusible material, contacting one end of a spring member with one end of said intermediate member and contacting the other end of said spring member with one end of said strut member.
 12. A method of assembling a sprinkler head in accordance with claim 11 wherein the step of inserting said temperature-responsive assembly includes the steps of engaging one end of said strut member with said valve member and engaging one end of the spring member with said bearing frame.
 13. A method of assembling a sprinkler head in accordance with claim 9 wherein the step of tightening said nozzle includes the step of threading said nozzle relative to said body orifice. 